1: 86 percent / dimethylformamide / 3 h / Heating 2: 92 percent / diisobutylaluminium hydride / toluene / 2 h / 45 °C 3: 97 percent / hydrazine monohydrate, potassium hydroxide / bis-(2-hydroxy-ethyl) ether / 1.) 80 deg C, 1 h, 2.) reflux, 2 h 4: 88 percent / acetic anhydride / 2 h / Heating View Scheme

1: 2.) PPA, 3.) cc HCl, / 1.) 150 deg C, 1 h, 2.) 150 deg C, 30 min, 3.) AcOH, H2O, reflux, 2 h, 2: 25 percent / hexamethylphosphoric acid triamide / 7 h / 160 °C View Scheme

2: 2.) PPA, 3.) aq. KOH 3: 36 percent / hexamethylphosphoric acid triamide / 5 h / 140 °C View Scheme

hydrogen; palladium on activated charcoal in acetic acid

1: 87 percent / Br2, Ag2SO4, cc H2SO4, / 1 h 2: 68 percent / H2, / PtO2, / acetic acid / Ambient temperature View Scheme

1: 2.) PPA, 3.) cc HCl, / 1.) 150 deg C, 1 h, 2.) 150 deg C, 30 min, 3.) AcOH, H2O, reflux, 2 h, 2: 30 percent / hexamethylphosphoric acid triamide / 6 h / 160 °C View Scheme